Combination lock



April 3 9 K. LECHNER 2,195,574

COIBINATION LUCK Filed Nov. 1, 193a INVENTOE KATHAR/NA LECHNER ATTORNEYSPatented Apr. .2, 1840 "UNITED S ATES 'I E T or -CE Y v 2,195,574 COMBINTION LooK Katharina Leclmer, Vienna, Germany.

Application November 1, 1938, Serial'No. 238,130 In Austriav November 3,1937 40mins. (01. 70-299) This invention relates to a combination lock,

with control .pieces including elements which are provided with twosuperposed stepped portions and which are actuated by outerkeysdesignated for instance by numerals and used to move the controlpieces in the axial direction.

In prior. art','such control pieces had the form of the-control (pieces..The control pieces were so arranged that in their displaced positiontheir longitudinal arms extend into the elongated slots.

' Loclm of this 'type'have the disadvantage that the control piecesmaymove in relation to the plates as .a result of even small shocks,with the result that the locking device may open or become inoperative.An object of the present invention is to eliminate this drawback byproviding means for securing the control pieces against unintendedrnov'er'n'ents', for instance, by arranging the control pieces uponslotted bolts havingthe form of split pins.

' Another drawback of locks known in prior art is the necessity of usingelements consisting of two layers and having the form of double crosses;

The cost of manufacturing these double crosses is very his particularlyas far as locks of small diniensions are concerned, and these crossesbreak easily irrespective of the material of which they are made.Furthermore, if the slots and openings of the plates are not quiteexact, the crosses may become jammed ormay damage the sharp edges of theslots. The'manufacture of such manufacturing costs are furtherincreased.

Another object of the present invention is toeliminate these drawbacksthrough the use of control pieces having T-shaped heads or heads t of ahalf-cross form.

In accordance with the present invention, the

cost of production may befurther decreased by substituting circularplates having cylindrical portions of different diameters arranged in a55 stepped formation for the aforesaid crosses, al-

crosses requires special skill, with the result that though mm case thecentralstep must bemade as small as possible. .1 i The drawingillustrates by way of example two 'forms'ofa lock constructed ina'ccordance'with the principles of the present invention; y In thedrawing: 1 i Figure "1 is a top view of a round .lock wherein,half'crosses are-used as control pieces, the cover and the uppercarrying plate being partly broken Figure Z'is a top 'view of a roundlock wherein H round or circular plates are used as control pieces, thecover andthe upper carrying plate being part, 1y broken off I Figure 31s a cross-section through the 1c1 15 shown in Figural onasomewhatlarger scale;

Figure 4 is a perspective iew of a control piece used in the deviceshown in Figures 1 and 3;" and Figure 5 is a perspective view 'of acontrol piece used in the device shown in Figure 2. a l Each of the twolocking devicesillustratednin the drawing comprises three superposedplates a,

1), and cwhich are situatedwithin a casingd The two outer plates a and care firmlyconnected with the casing and are therefore immovable, 25while themiddle plate 11' is rotatable about its central axis. Themiddle plate'b'has a square central opening intoqwhich a square portionof a pinf is fitted, so that the plate I) is rotated along with, the pin1 e 30 Obviously, the pin f may be made immovable and the plate I) maybe caused torotate around thepini Y A hook 2 also has a square openinginto which a square portion of the pin f'is fitted, so that the hook erotates along with the plate 1b andthe pin 1. Obviously, the hook e mayconstitute a part of the plate I).

A number of control pieces g are arranged in a circle around the centralaxis of the plates.

The control pieces shown in Figures 1, 3, and 4 comp-rise an upperlarger head portion 91 and a smaller lower head portion 02 which havethe form of a T or a half cross. i Each of the control pieces isprovided with a slotted bolt n having the form of a split pin;

The plates at, b, and 0 have openings the form of which corresponds tothat of the control pieces.

The upper plate a and thelowest plate 0 have openings hi correspondingto the larger head portion 91 of the control pieces 9 while the middlerotary plate b has openings hr which are integral with elongated slotshz into which the portions oz of the control pieces may be fitted.

The control pieces are actuated by means of .plates a and c.

keys i which are depressed manually and which are returned into theiroriginal position by means of springs. The keys 1'. are arranged in acircle and may be designated by numerals or other insignia. 1 i

The device used for returning the displaced control pieces to theiroriginal position comprises a returning plate k, which may be raised bymeans of a fiangel constituting a part of the pin 1, which is providedwith a handle m so that it can be easily grasped and pulled in the axialdirection. Furthermore, the same handle m may be turned to rotate themiddle plate b, which is rotatable along with the pin 1.

Due to the provision of the slotted bolts n, the control pieces are heldin their proper position by the spring action of these bolts, so that itis possible to move them relatively to the plates only by acomparatively strong pressure or action.

The device is operated as follows:

The control pieces are originally set-in the upper plate a in suchmanner that most of them have their larger upper portions g1 situated inthe openings hl of the upper fixed plate a, while their smaller headportions 92 are situated in the openings ha of the movable plate b. Ifall the control pieces were located in this position, the middle plate bcould be rotated relatively to the However, some of the control piecesare arranged in such manner that their smaller head pieces 112 aresituated in the openings hl of the upper plate a, while their largerhead portions g1 are situated-in the openings hi of the middle plate I).Then it is not possible to move the middle plate b any more, since thelastmentioned control pieces lock this plate against movement.

For example, the positions of three control pieces actuated'by keys inumbered 2, I, and 3, may be arranged in reverse positions in thismanner.

In order to open the lock, it is necessary to move these three reversedcontrol pieces in such manner that they will not lock the middle plate bany more. This can be achieved by moving the smaller head portions oz ofthe three reversed control pieces into the openings he of the middleplate 12 and by moving the larger head portions 911 of these pieces intothe openings ill of the lowermost plate '0. In order to move thereversed control pieces to these positions, it is necessary to depressthe keys numbered 2, l, and 3 until the reversed control pieces aremoved inwardly to the extent of the thickness of a plate.

If the operator by mistake depresses the wrong control piece, so thatone of the three reversed control pieces is not moved into the correctposition, the lock remains locked and does not open even if later on heoperates the correct key.

In order to open the lock, it is necessary first to reset all the keysand control pieces by raising the returning-plate Ia and then to pressthe correctly numbered keys, whereupon the middle plate can be turnedto, unhook the hook e.

The described lock can be used not only for locking doors of all kindsbut also for motorcars, as a lock for the starting device, the car door,the ignition, and the like.

What is claimed is:

1. In a combination lock consisting of stepped control pieces in twolayers displaceable by means of keys marked on their outer face betweenand vertically .to carrying plates, in which the said control pieces areheld by the spring action of split pin-like slotted bolts in theirproper position.

2. In a combination lock consisting of stepped control pieces in twolayers displaceable by means of keys marked on their outer face betweenand vertically to carrying plates, in which the said control pieces areof a T-head form.

3. In a combination lock consisting of stepped control pieces in twolayers displaceable by means of keys marked on their outer face betweenand vertically to carrying plates, in which the saidcontrol piecesconsist of circular plates with a central boltlike nose.

4. In a combination lock, in combination, three 1 superposed plates,movable control pieces extending perpendicularly to said plates, each ofsaid control pieces having two portions adapted to engage openingsformed in two of said three plates, one of said three plates beingrotatable relatively to the other two plates, each of said controlpieces also having mechanical locking means maintaining it in positionrelatively to said plates to prevent the shifting of the control piece;and separate keys for actuating said control pieces.

KATHARINA LECHNER.

